* Bump maintenance branches to 3.3.7 (#1061)

Ruby 3.3.7 has been released:
https://www.ruby-lang.org/en/news/2025/01/15/ruby-3-3-7-released/

Bump 3.3 branch from 3.3.6 to 3.3.7:
ruby/ruby@v3_3_6...v3_3_7

There seems to be no change to the syntax.

Author: koic

.github/workflows/test.yml

@@ -17,7 +17,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ["3.0.7", "3.1.6", "3.2.6", "3.3.6", "jruby-9.2"]
+        ruby: ["3.0.7", "3.1.6", "3.2.6", "3.3.7", "jruby-9.2"]
         test_command: ["bundle exec rake test"]
         include:
           - ruby: "head"
@@ -26,7 +26,7 @@ jobs:
             test_command: "bundle exec rake test || true"
           - ruby: "3.2.6"
             test_command: "./ci/run_rubocop_specs || true"
-          - ruby: "3.3.6"
+          - ruby: "3.3.7"
             test_command: "./ci/run_rubocop_specs || true"
     steps:
     - uses: actions/checkout@v4

lib/parser/current.rb

@@ -111,7 +111,7 @@ def warn_syntax_deviation(feature, version)
     CurrentRuby = Ruby32
 
   when /^3\.3\./
-    current_version = '3.3.6'
+    current_version = '3.3.7'
     if RUBY_VERSION != current_version
       warn_syntax_deviation 'parser/ruby33', current_version
     end